North Korea blamed its recent Internet outage on the United States yesterday and hurled racially charged insults at President Barack Obama over the hacking row involving the movie The Interview.

North Korea's powerful National Defence Commission, which is led by Kim Jong-un and is the country's top governing body, said Obama was behind the release of the comedy that depicts Kim's assassination. The commission described the movie as illegal, dishonest and reactionary.

"Obama always goes reckless in words and deeds like a monkey in a tropical forest," an unidentified spokesman at the commission's policy department said in a statement carried by the country's official Korean Central News Agency.

The White House's National Security Council declined to comment yesterday.

North Korea has denied involvement in a crippling cyberattack on Sony Pictures but has expressed fury over the comedy. Sony Pictures initially called off the release of the film, citing threats of terror attacks against US movie theatres. Obama criticised Sony's decision, and the movie opened last week.

It isn't the first time North Korea has used crude insults against Obama and other top US and South Korean officials. Earlier this year, North Korea called US Secretary of State John Kerry a wolf with a "hideous" lantern jaw, and South Korean President Park Geun-hye a prostitute. In May, the North's official news agency published a dispatch saying Obama has the "shape of a monkey."